A current-source single-stage multi-input high-frequency-link grid-connected inverter and a three-mode one-cycle control strategy are proposed and deeply investigated in this paper. The inverter contains multiple current-source inverting units, a multi-input high-frequency transformer, and a cycloconverter. It achieves single-stage power conversion and high-frequency galvanic isolation with a simple circuit structure. The control strategy adds a by-pass switch to the energy storage inductor. It has energy-storing, energy-releasing, and three by-pass operation modes in a low frequency cycle. Through calculating the energy-releasing duty cycle in real time, the magnetic saturation problem of current-source inverters is solved and the output waveform quality is greatly improved. Soft-switching of the converter, a transfer function block diagram, and the design of the main circuit parameters are achieved. The simulation of a three-input inverter and experiment on a two-input inverter verify the feasibility and advancement of the proposed circuit topology and control strategy.

本文提出并深入研究了电流源单级多输入高频环节并网逆变器和三模单周期控制策略。该逆变器包含多个电流源逆变单元、一个多输入高频变压器和一个循环变流器。它以简单的电路结构实现了单级功率转换和高频电流隔离。该控制策略为储能电感增加了一个旁路开关。具有储能、放能、低频循环三种旁路运行模式。通过实时计算能量释放占空比，解决了电流源逆变器的磁饱和问题，大大提高了输出波形质量。转换器的软开关，传递函数框图，并实现了主电路参数的设计。三输入逆变器的仿真和二输入逆变器的实验验证了所提出的电路拓扑和控制策略的可行性和先进性。